CRX brakes
 

Hi you all
I just can’t believe the trouble I’m having with this 91 CRX si. I’m trying to change the front disk pads which usually is a very simple procedure, right? But on this CRX it’s murder. Normally, a regular C-clamp is sufficient to press back the caliper’s piston to allow the new thicker pads on. But I can’t press the piston back.
The bleeding screw on the caliper's rusted on tight, so I loosened the brake line screw instead thinking that maybe it's the fluid pressure, which doesn't make sense, but oh well. But that didn't work either anyway.
Anybody with any suggestions?

If anybody has the answer, thanks in advance, Paul